Yankee Group has made a realiability survey and found that Windows 2003 Server is a more reliable server operating system than Linux. Windows 2003 server has 20 percent more uptime than Red Hat Enterprise Linux, but HP-UX and Sun Solaris have more uptime than Windows 2003 Server.
Yankee Group offers a reason for the problem: “the scarcity of Linux and open source documentation”.
Surprisingly, the survey wasn’t sponsored by Microsoft, but was made by Laura DiDio, who is often viewed as being very critical of the Open Source movement and community. You can see her in a video hosted by Microsoft.